187681221079 has 16 divisors (see below), whose sum is σ = 205829406720. Its totient is φ = 169715475360.

The previous prime is 187681220959. The next prime is 187681221083. The reversal of 187681221079 is 970122186781.

It is a cyclic number.

It is not a de Polignac number, because 187681221079 - 2⁹ = 187681220567 is a prime.

It is a super-4 number, since 4×187681221079⁴ (a number of 46 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (187681221379) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2703882 + ... + 2772424.

It is an arithmetic number, because the mean of its divisors is an integer number (12864337920).

Almost surely, 2^187681221079 is an apocalyptic number.

187681221079 is a deficient number, since it is larger than the sum of its proper divisors (18148185641).

187681221079 is a wasteful number, since it uses less digits than its factorization.

187681221079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69870.

The product of its (nonzero) digits is 677376, while the sum is 52.

The spelling of 187681221079 in words is "one hundred eighty-seven billion, six hundred eighty-one million, two hundred twenty-one thousand, seventy-nine".